The invention relates to a quick-action connection for retaining an insertion part in an orifice of a carrier, especially for retaining a holding nipple receiving one end piece of a Bowden cable sleeve in a vehicle body wall. The insertion part can be inserted into the orifice by means of a tenon-shaped extension piece to a limited depth. The extension piece has a peripheral groove carrying a resiliently radially flexible retaining ring which is adapted to abuttingly engage the carrier adjacent the orifice by one of its end faces.
A quick-action connection of this type has been contemplated in vehicle-building, for example for mounting a holding nipple in the front end wall of the body of passenger cars.
The holding nipple receives one end piece of the sleeve of a Bowden cable, and the Bowden cable is guided axially through the holding nipple. The steel retaining ring held in the peripheral groove of the tenon-shaped nipple extension piece and securing the holding nipple axially in the end wall is slotted along a generatrix, so that it can be compressed in the radial direction when the nipple is mounted and, in the prestressed state, introduced, together with the nipple extension piece, into the particular end-wall orifice and pushed through this.
As soon as the portion of the nipple extension piece carrying the retaining ring emerges again on the side of the end wall located opposite the insertion side, the retaining ring springs open radially and is consequently located partially inside and partially outside the peripheral groove. At the same time, the retaining ring engages, by means of part of one of its annular end faces, over the adjacent edge of the insertion orifice present in the end wall and thus forms a stop which automatically secures the holding nipple axially in the wall orifice. The retaining ring thus allows blind mounting of the holding nipple which can be carried out quickly from one side of the end wall.
One disadvantage which has emerged in such a quick-action connection is that the nipple retaining means give way as soon as a bending moment is exerted on the holding nipple. The reasons for this is that, so that the nipple extension piece can be pushed through the end-wall orifice easily, it is arranged in the latter with a clearance fit, and the retaining ring, because of its slotting, is not capable of opposing an appropriate resistance moment to bending moments. In particular, the retaining ring is subjected to torsion of its peripheral part located opposite the ring slot, and its retaining effect then decreases sharply. Another disadvantage is that, because of the slotted annular shell, the radial expansion of the retaining ring on the periphery and consequently the support of the retaining ring against the end wall are uneven.
An object on which the invention is based is to provide a quick-action connection of the type mentioned above, the retaining ring of which performs its retaining function fully even under bending moments exerted on the insertion part, expands uniformly in the radial direction over its entire periphery when it is relieved of stress or springs open, and consequently provides a correspondingly favorable supporting base for the insertion part of the carrier.
According to the invention, this object is achieved by constructing the retaining ring shell to be closed in the peripheral direction and to be configured in the form of a meander by forming slots extending from the end faces of the ring in the axial direction along a portion of the length of the ring.
The annular shell closed in the peripheral direction and extending in the form of a meander makes it possible to obtain a design of the retaining ring which is flexible in the radial direction, so that the latter can be compressed radially during the assembly of the insertion part, in order to introduce its tenon-shaped extension piece into the particular carrier orifice.
When the retaining ring prestressed in this way then comes free of the periphery of the carrier orifice again during assembly, it springs open to a larger diameter, if appropriate to its original diameter, and in the axial direction provides, via its end faces, an essentially rigid support which is uniform over the entire ring periphery.
At the same time, because of the annular shell closed in the peripheral direction, the restoring forces exerted in the radial direction are equal over the entire ring periphery, and, depending on the shape of the meander design, a desired spring behavior when the retaining ring springs open can be achieved.
In a design of the retaining ring according to one preferred embodiment having slots of equal length extending from both end faces, a uniform restoring stress can be obtained in the radial direction over the rings entire shell length.
In a ring designed according to another preferred embodiment, the slots extend an unequal length from the respective ring end faces. With this design an asymmetric stress behavior can be obtained deliberately in the radial direction.
In preferred advantageous embodiments the slot-like recesses have a decreasing peripheral width in the direction away from their openings at one of the respective ring end faces.
In particularly advantageous designs the retaining rings are constructed of concial shape with the insertion end having the minimum diameter. With this design it is simple to insert the retaining ring into the carrier orifice.
In especially preferred embodiments, the annular end face of the retaining ring which faces the carrier wall when inserted is tapered conically inwards. In this case, the depth of insertion of the insertion part into the carrier orifice and the width of the peripheral groove on the extension piece of the insertion part can be coordinated with one another, in such a way that the conical annular end face of the not completely expanded retaining ring is supported merely on the peripheral edge of the carrier orifice or the groove wall of the peripheral groove adjacent to it.
As a result of the radial ring prestress still effective, a wedge effect and therefore at the same time a tolerance compensation are in this case achieved between the annular end face and the respective peripheral edge, so that a play-free and suitably sealed axial retention of the insertion part of the carrier orifice is guaranteed.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.